Check this out
2010 E63, 54K miles:
- ROW boxes
- AFE Dry filters
- Resonator & 2nd Cat Delete (X-pipe)
- Eurocharged Tune
Note stock baseline was about 390; 399 after first 3 items installed.

 

Is that a 12hp gain and a couple ft/lbs of torque lost on the tune?

 

Yes, not sure it has anything to do with the x-pipe. Also, I didn't get a record of any torque difference between stock and x-pipe.

 

How much did the tune cost you ? I hope you got a good deal

 

Yeah, there was a 30% sale ; reg $1200. I can definitely tell a difference with +21hp, but I think I have to get headers...

 

What results are most getting?

 

Subscribed. I had a Eurocharged V4 tune on my CLK BS and would be interested in knowing the gains on the M156 without any extra mods beyond a euro airbox and filters.

Yours seems like a small gain with the x-pipe mod and all of the other items I mentioned above. I would hope you could get 9hp with the tune by itself, but maybe there's not much room with the OEM tuning...